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I keep seeing sites mentioning that the directory that you execute 'python ' get added to the python path. For example on http://www.stereoplex.com/blog/understanding-imports-and-pythonpath, the author cd's to the /tmp folder then does 'print(sys.path)' and lo and behold, the /tmp folder appears in the path list. Here is me trying this out on my system (with 2.6.6 installed):

example structure: 

app/
  mymodule.py
  inner_folder/
    myscript.py

in myscript.py contains the line: 

import mymodule.py

what I did:

cd app
python inner_folder/myscript.py # ImportError

Since I am executing the interpreter from the app/ directory, shouldn't 'app' be added to the python path? This is how a lot of the docs I have been reading have specified the behaviour should be.

Please enlighten!

(I have temporarily solved this by manually adding the folder I want into the environment but don't want to rely on that forever. Since many sites say this can be done, I'd like to reproduce it for myself)

Aman
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trinth
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2 Answers2

76

It is the script's directory that is added, not the current directory. If you turn inner_folder/ into a package then you can use python -m inner_folder.myscript in order to run the script while having app/ added to sys.path.

Ignacio Vazquez-Abrams
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  • +1: indeed, even with the import fixed, this is the real solution. – André Caron Jun 20 '11 at 19:40
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    Thank you for clarifying. I knew the script's directory was added but the only reason I believed that the "current directory" was added as well was because it used to work. I swear! Something must have happened to make it stop working. I don't recall modifying the PYTHONPATH in any way so this is why I asked this question. – trinth Jun 20 '11 at 22:45
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    When running Python 2.7 in mac OS 10.7.5, the current directory is added for me, and the original example code works. – Cypress Frankenfeld Jun 19 '13 at 18:46
  • @CypressFrankenfeld, not sure why your current directory is added, but just for a sanity check, you might want to first execute `unset PYTHONPATH`. – Garrett Jun 20 '15 at 05:18
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    @CypressFrankenfeld: in python versions prior to 3.4, an empty PYTHONPATH resulted in '.' being added to sys.path. See https://docs.python.org/3/whatsnew/3.4.html#changes-in-python-command-behavior – ForeverWintr Sep 09 '16 at 21:41
4

Whether or not the current directory is in sys.path, import statements usually look like:

import mymodule

The code you wrote looks like:

import 'mymodule.py'
André Caron
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